Malicious PDF — malware analysis report

Static analysis result for SHA-256 3943bd32c1a3c305…

MALICIOUS

PDF

79.4 KB Created: 2021-09-16 13:03:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8a53b9f0e62c644ffd7f4a1e706487a3 SHA-1: 73aaac1dc54d90c796b6bffe28e5f8cb6f2f4bee SHA-256: 3943bd32c1a3c305130e75c91a174fe647844295efc1a16982f33422158b2343
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to other PDF files hosted on various domains, suggesting a link farm or redirection scheme. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to distribute malicious content or manipulate search engine results.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://hzyixiangchem.com/upload/files/44031112903.pdf In PDF document text
    • http://nattukoottam.com/userfiles/file/76200680699.pdfIn PDF document text
    • https://deesudcoolingtower.com/userfiles/file/10339083453.pdfIn PDF document text
    • https://amatnieks.com/pictures/image/poxalawibosuxikufizex.pdfIn PDF document text
    • https://immsac.pe/sgi_userfiles/userfiles/files/lumanavetenazeged.pdfIn PDF document text
    • https://mkontakt.com/dat/file/zusobu.pdfIn PDF document text
    • https://residenciasanamaro.es/userfiles/files/bedugutezanapurara.pdfIn PDF document text
    • http://daphongthuyhueminh.com/uploads/image/files/kafekuxilisibuxidepoxo.pdfIn PDF document text
    • http://alkanboya.com/files/file///xekiwozalenupenafax.pdfIn PDF document text
    • http://bowie.abwingsmd.com/uploads/files/pezefagofukelixiriwuw.pdfIn PDF document text
    • http://photopuzzle.net/userData/board/file/15518475966.pdfIn PDF document text
    • http://balalajka.nu/media/nejakesagepinosovupifum.pdfIn PDF document text
    • http://smartdeal.pl/files/upload/files/41721456397.pdfIn PDF document text
    • https://www.peltonfell.org.uk/ckfinder/userfiles/files/29849143764.pdfIn PDF document text
    • https://citytrafik.nu/images/file/3718806036.pdfIn PDF document text
    • https://asken.as/bilder/file/witurusegikajorugipejen.pdfIn PDF document text
    • http://alajwakh.com/uploaded_files/userfiles/files/42022336740.pdfIn PDF document text
    • https://dottoridegregorio.it/public/file/nutonupuxiroru.pdfIn PDF document text
    • http://www.jucadent.es/ckfinder/userfiles/files/dagolijanoxefuzuni.pdfIn PDF document text
    • https://rugsinc.in/UserFiles/files/64501802763.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132fca718375---guriludodo.pdfIn PDF document text
    • https://renewone.de/files/85304576331.pdfIn PDF document text
    • https://klcmekatronik.com/ckfinder/userfiles/files/sidefuwofuvujojarus.pdfIn PDF document text
    • http://www.taimaobi.com/admin/ckfinder/userfiles/files/fafofufaguwuxalawesatumu.pdfIn PDF document text
    • http://peggylittlelawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/50733498862.pdfIn PDF document text
    • http://hrudolf.com/userfiles/53374404909.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=tubidy+music+video+downloadPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ccd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCD8 19664 bytes
SHA-256: 18ab1837f023d5b09b2d44030f16c9130540444d172df3ad29d84cde4a2a9b27
font_01_sfnt_off0000fe71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE71 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011688.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11688 10804 bytes
SHA-256: 884ebe0afc0b1f6472b009a20c6067e6c895726eb2152d715d2094f0b5c6c1d5